1. Field of the Invention
The present invention relates to a method of stopping an absorption refrigerator and particularly, a method of stopping an absorption refrigerator in such a manner that the refrigerator will be able to promptly be restarted upon being switched on.
2. Description of the Related Art
In an air-cooling absorption refrigerator using water as a refrigerant and lithium bromide as an absorbent, the absorbent in an absorbent solution is likely to be crystallized during non-running of the refrigerator. For preventing the crystallization of the absorbent, it is common that, when a stopping operation is conducted, circulation pumps for the absorbent solution and the refrigerant are not immediately turned off but are kept running for a while to allow the absorption solution to absorb refrigerant vapor for decreasing the concentration of the absorbent and/or to mix the highly concentrated solution with a diluted solution for dilution of the absorbent solution. For example, a conventional method of stopping the operation of an absorption refrigerator is disclosed in Japanese Patent Laid-open Publication No. Hei 8-226722 in which the diluting operation is terminated when the temperature of a refrigerant drops to a predetermined degree, instead of a known diluting operation controlled simply with a timer, thus avoiding useless running of the refrigerator and decreasing the consumption of electric power to minimize the running cost.
In such a conventional method of stopping the operation, the absorbent solution is saved in a diluted state for preventing the crystallization during stopping of the refrigerator and, when the refrigerator is restarted, the diluted absorbent solution has to be converted by separation of the refrigerant therefrom to a high concentration of the solution for producing a desired level of performance. This requires a length of time from the start up to the normal running. In addition to taking the length of time, such a wasteful operation is needed that the absorbent solution with a concentration suitable for normal running is diluted by using an amount of energy upon stopping the refrigerator and the solution has to be converted back by using another amount of energy from a diluted state to its original suitable concentration when starting again. Accordingly, the efficiency of energy consumption will be lowered.